Abstract: To counter the problems existing in sub-level caving mining, the behaviour of caved ore massand its effect on the ore loss and dilution has been analysed theorically. Throgh the small-scale and industrial tests, the concept of"caved ore mass"is presented, and the behaviour of the caved ore mass is determined.It is pointed out that the drawing mass, bulky mass and caved mass are considered as a whole connectedeath other. The blasting problem must be analysed comprehensively with the blasting caving. Throgh blstcontrolling the behaviour and effectiveness of caved ore pile formed by draWing mass, the talled behaviourof ore rnass, caved mass and remnant, can be achieved to decrease the ore loss and dilution.